import matplotlib.pyplot as plt

x = [1,2,3,5,6,7,8,9,10,12,13,14,15,16,18,19,21,22]
y = [100,90,80,60,60,55,60,65,70,70,75,76,78,79,90,99,99,100]

plt.scatter(x, y)

import numpy

mymodel=numpy.poly1d(numpy.polyfit(x,y,3))
myline=numpy.linspace(min(x),max(x),100)

plt.plot(myline,list(map(mymodel,myline)))

plt.show()

from sklearn.metrics import r2_score
print("拟合度",r2_score(y,mymodel(x)))